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probes::CiscoRTTMonTcpConnectS(m3o)kePpirnogbes::CiscoRTTMonTcpConnect(3)
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probes::CiscoRTTMonTcpConnect - Probe for SmokePing
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+ CiscoRTTMonTcpConnect
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menu = MyRouter->TCPVictim
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title = RTTMon TCP connect from MyRouter to TCPVictim
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host = TCPVictim.foobar.com.au
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probe=CiscoRTTMonTcpConnect
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ioshost = RTTcommunity@Myrouter.foobar.com.au
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DDEESSCCRRIIPPTTIIOONN
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A probe for smokeping, which uses the ciscoRttMon MIB
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functionality ("Service Assurance Agent", "SAA") of Cisco
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IOS to measure TCP connect times between a Cisco router
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and a TCP server. The measured value is the time is the
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time to establish a TCP session, i.e. the time between the
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initial "SYN" TCP packet of the router and the "SYN ACK"
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packet of the host. The router terminates the TCP session
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immediately after the reception of "SYN ACK" with a "FIN"
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The (mandatory) host parameter specifies the IP host,
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which the router will connect to. This can be a DNS name,
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the smokeping host can resolve or a dotted-quad IP
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The (mandatory) ioshost parameter specifies the Cisco
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router, which will establish the TCP connections as well
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as the SNMP community string on the router.
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The (optional) port parameter lets you configure the des-
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tination TCP port on the host. The default is the http
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The (optional) iosint parameter is the source address for
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the TCP connections. This should be one of the active (!)
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IP addresses of the router to get results. IOS looks up
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the target host address in the forwarding table and then
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uses the interface(s) listed there to send the TCP pack-
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ets. By default IOS uses the (primary) IP address on the
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sending interface as source address for a connection.
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The (optional) tos parameter specifies the value of the
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ToS byte in the IP header of the packets from the router.
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Multiply DSCP values times 4 and Precedence values times
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32 to calculate the ToS values to configure, e.g. ToS 160
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corresponds to a DSCP value 40 and a Precedence value of
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5. Please note that this will not influence the ToS value
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in the packets sent by the the host.
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IIOOSS VVEERRSSIIOONNSS
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This probe only works with Cisco IOS 12.0(3)T or higher.
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It is recommended to test it on less critical routers
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IINNSSTTAALLLLAATTIIOONN
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To install this probe copy ciscoRttMonMIB.pm to
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($SMOKEPINGINSTALLDIR)/lib and CiscoRTTMonTcpConnect.pm to
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($SMOKEPINGINSTALLDIR)/lib/probes. V0.97 or higher of
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Simon Leinen's SNMP_Session.pm is required.
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The router(s) must be configured to allow read/write SNMP
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access. Sufficient is:
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snmp-server community RTTCommunity RW
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If you want to be a bit more restrictive with SNMP write
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access to the router, then consider configuring something
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access-list 2 permit 10.37.3.5
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snmp-server view RttMon ciscoRttMonMIB included
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snmp-server community RTTCommunity view RttMon RW 2
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The above configuration grants SNMP read-write only to
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10.37.3.5 (the smokeping host) and only to the ciscoRttMon
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MIB tree. The probe does not need access to SNMP variables
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outside the RttMon tree.
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The probe establishes unnecessary connections, i.e. more
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than configured in the "pings" variable, because the
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RTTMon MIB only allows to set a total time for all connec-
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tions in one measurement run (one "life"). Currently the
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probe sets the life duration to "pings"*2+3 seconds (2
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secs is the timeout value hardcoded into this probe).
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http://people.ee.ethz.ch/~oetiker/webtools/smokeping/
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http://www.switch.ch/misc/leinen/snmp/perl/
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The best source for background info on SAA is Cisco's doc-
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umentation on http://www.cisco.com and the CISCO-RTTMON-
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MIB documentation, which is available at:
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ftp://ftp.cisco.com/pub/mibs/v2/CISCO-RTTMON-MIB.my
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Joerg.Kummer at Roche.com
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1.35pre1 2005-0p1r-o0b4es::CiscoRTTMonTcpConnect(3)